des_expand_key(9)

✨ NAME ✨

okay bestie, welcome to the des_expand_key(9) page in the Kernel API Manual 🫶 — this is the function that expands a DES input key into a key schedule. literally its whole job. 💅

🌸 SYNOPSIS 🌸

no cap, here's the signature exactly:

int des_expand_key (struct des_ctx *ctx , const u8 *key , unsigned int
       keylen );

🎀 ARGUMENTS 🎀

• ctx — the key schedule. that's the vibe.
• key — buffer containing the input key. the actual key material goes here, bestie.
• keylen — size of the buffer contents. yes, it matters.

💖 RETURN 💖

• 0 — success. we love to see it. ✨
• -EINVAL — the input key is rejected. not iconic, but that's the answer.
• -ENOKEY — the key is accepted but has been found to be weak. so it's accepted and flagged, and that's why you get -ENOKEY. 😭

🦋 SEE ALSO 🦋

• Kernel file ./include/crypto/des.h
• des3_ede_expand_key(9)

byeee 🧚💜 — this page came from source/version ./include/crypto, dated October 2026, and it's the des_expand_key(9) page. mwah 💋